FIG. 14 is a front view of a prior art wedge plate clutch 200. Clutch 200 includes inner ring 202; outer ring 204 located radially outwardly of inner ring 202; circumferentially aligned wedge plate segments 206 radially disposed between inner ring 202 and outer ring 204; and snap ring 208. Snap ring 208 includes circumferential gap 210. That is, snap ring 208 is discontinuous at gap 210.
As is known in the art, for a disconnect mode for clutch 200, in which inner rings 202 and 204 are rotatable with respect to each other, it is necessary to prevent frictional contact between segments 206 and inner ring 202, which can result in an unintended transition to a connect mode for clutch 200, in which ring 202, segments 206, and ring 204 are non-rotatably connected. Snap ring 208 is provided with the intent to perform the preceding function. However, once installed, snap ring 208 assumes an ovoid, rather than a circular shape, about major axis MA. As a result, snap ring 208 urges only a portion of segments 206 radially outwardly into contact with outer ring 204 and out of contact with inner ring 202. For example, segments 206J, 206A bracketing one end of major axis MA at gap 210, and segments 206D and 206E and 206F and 206G, bracketing the other end of major axis MA, are urged into contact with ring 204 by snap ring 208. Segments 206B, 206C, 206H, and 206I: are not urged into contact with ring 204 by snap ring 208; and during the disconnect mode, may contact ring 202, initiating the unintended transition to the locked mode. It should be understood that other groupings of segments 206 can be urged into contact with ring 204 depending for example on where gap 210 is placed; however, there is no arrangement in which snap ring 208 urges all of segments 206 into contact with ring 204.